Question: In his chemistry class, Luis took 6 exams. His scores were 77, 84, 94, 83, 91, and 81. What was his average score on the exams?
Solution: The average is the sum of his scores divided by the number of scores. There are 6 scores and their sum is $77 + 84 + 94 + 83 + 91 + 81 = 510$ His average score is $510 \div 6 = 85$.